a Study of a Tidally Interacting BCD Pair: ESO 435-IG20 and ESO435-IG16

Abstract

We investigate Hi data for a pair of blue compact dwarf galaxies (BCDs), ESO 435-IG20 and ESO 435-IG16, obtained with the Australia Telescope Compact Array. The outer Hi disk is highly disturbed and asymmetric in both galaxies showing a gas tail and/or a broad/extended gas disk on only one side. Based on their low-density surroundings and small projected distance (<80 kpc) at a similar redshift, we conclude that tidal interaction between these two BCDs is responsible for the morphological and kinematical peculiarities in Hi. We also investigate their star formation rates using H and UV imaging data to probe their interaction history.